pyATS Install & Setup

pyATS (Python Automated Test Systems) is a Python based test automation infrastructure framework that was originally developed for internal Cisco engineering use. pyATS is at the core of Cisco's Test Automation Solution. It is the de-facto test framework for internal Cisco engineers across different platform/functions, running millions of CI/CD, sanity, regression, scale, HA, solution tests on a monthly basis; and by thousands of network engineers and developers world-wide, outside of Cisco.

Step 1 - Change Directories Back To Main Project Directory

While still at your VSCode terminal, change directories back to main project directory:

    
        cd /home/cisco/Documents/nxapilab/
    

Step 2 - Install pyATS

pyATS is installed via pip. To install the full pyATS framework, using the full keyword as you'll do in this lab:

    
        pip install 'pyats[full]'==24.1
    

Step 3 - Verify pyATS Install

Verify pyATS install with pyats version checker:

    
        pyats version check
    

    You are currently running pyATS version: 24.1
    Python: 3.11.6 [64bit]

    Package                      Version
    ---------------------------- -------
    genie                        24.1
    genie.libs.clean             24.1
    genie.libs.conf              24.1
    genie.libs.filetransferutils 24.1
    genie.libs.health            24.1
    genie.libs.ops               24.1
    genie.libs.parser            24.1
    genie.libs.robot             24.1
    genie.libs.sdk               24.1
    genie.telemetry              24.1
    genie.trafficgen             24.1
    pyats                        24.1
    pyats.aereport               24.1
    pyats.aetest                 24.1
    pyats.async                  24.1
    pyats.connections            24.1
    pyats.contrib                24.1
    pyats.datastructures         24.1
    pyats.easypy                 24.1
    pyats.kleenex                24.1
    pyats.log                    24.1
    pyats.reporter               24.1
    pyats.results                24.1
    pyats.robot                  24.1
    pyats.tcl                    24.1
    pyats.topology               24.1
    pyats.utils                  24.1
    rest.connector               24.1
    unicon                       24.1
    unicon.plugins               24.1
    yang.connector               24.1

Step 4 - Create Tests Directory

Create a tests directory in your project. This directory name is common for including tests.

  
      mkdir tests
      mkdir -p tests/results
      touch tests/results/.keep
      cd /home/cisco/Documents/nxapilab/tests/
  

Step 5 - pyATS Testbed YAML File

pyATS offers a topology module for interacting with devices. This is primarily done through a topology or testbed YAML file that is loaded at runtime. This file has all the device information, connection information, metadata, etc for how to interact with devices in your environment.

While still in VSCode, create a testbed YAML file that includes the switches that are part of your staging or test fabric that you have programmatically been building out as a VXLAN EVPN fabric.

  
      code -r /home/cisco/Documents/nxapilab/tests/staging-testbed.yaml
  

Step 6 - pyATS Testbed YAML File

Populate the staging-testbed.yaml file with the connection information for interacting with your switches. You will notice the testbed file has a name on line 3. Starting on line 5, there are default credentials defined for device access. This can be made more secure in your own environment using environment variables or pyATS secret strings. Lines 10, 25, and 40 under the devices key are where your device information is defined. Under each device, the os key set to nxos and platform key set to n9k are the important pieces for pyATS using the correct device connector, i.e. correct connector that expects the correct type of cli prompt.

Lastly, the actual connections are defined. The names for the connections used in this lab, ssh and rest are arbitrary names and can be anything, however, it is good practice to align with the type of connection. Notice two things with the the rest connection; it makes use of the rest connector package that was installed above, and it's set as the default connection.

    
        ---
        testbed:
          name: NX-API Staging Lab
          alias: Staging
          credentials:
            default:
              username: admin
              password: cisco.123
        devices:
          staging-spine1:
            alias: n9kv-s1
            type: switch
            os: nxos
            platform: n9k
            connections:
              defaults:
                via: rest
              ssh:
                protocol: ssh
                ip: 10.15.6.11
              rest:
                class: rest.connector.Rest
                protocol: https
                ip: 10.15.6.11
          staging-leaf1:
            alias: n9kv-l1
            type: switch
            os: nxos
            platform: n9k
            connections:
              defaults:
                via: rest
              ssh:
                protocol: ssh
                ip: 10.15.6.12
              rest:
                class: rest.connector.Rest
                protocol: https
                ip: 10.15.6.12
          staging-leaf2:
            alias: n9kv-l2
            type: switch
            os: nxos
            platform: n9k
            connections:
              defaults:
                via: rest
              ssh:
                protocol: ssh
                ip: 10.15.6.13
              rest:
                class: rest.connector.Rest
                protocol: https
                ip: 10.15.6.13
        

    

After successfully populating staging-testbed.yaml with the above connection information, save your staging-testbed.yml file using Ctrl+s on the Windows keyboard or by clicking File then Save.

Once saved, close staging-testbed.yaml by clicking the small x (close button) to the right of the file tab:

Continue to the next section to create tests using pyATS AEtest.